In recent years, there have been actively developed vitreous silica crucibles which are used to pull a silicon single crystal and can, with a simple structure, prevent the upper end of a sidewall from falling inward. As an example of such a technology, Patent Document 1 discloses a vitreous silica crucible which is used to pull a silicon single crystal and which has a circular groove on the perimeter of a sidewall and above the initial melt line. This groove is provided in a position below the upper end of a carbon susceptor.
There have been also actively developed methods for, when manufacturing a single crystal by the Czochralski method, efficiently and reliably designing pull-up conditions under which solidification is less likely to occur in positions other than the growth interface of the growing single crystal which is being pulled up. As an example of such a technology, Patent Document 2 discloses a method for designing single crystal pulling conditions when growing a single crystal from a raw material melt-containing crucible by the Czochralski method. In this method for designing single crystal pulling conditions, an in-melt average temperature gradient G (K/cm) is obtained by dividing an in-melt temperature difference ΔT (K) between the outer peripheral surface of a single crystal to be grown and the inner wall of the crucible obtained by overall heat transfer analysis by the horizontal distance L (cm) on the melt surface between the outer peripheral surface of the single crystal to be grown and the inner wall of the crucible; and then pulling conditions are set based on the relationship between the in-melt average temperature gradient G and the incidence of solidification which occurs in positions other than the growth interface of the growing single crystal which is being pulled up.